1. Field of the Invention
The present invention relates to a silver halide color photographic photosensitive material and, more particularly, to a color photographic photosensitive material which can reproduce various hues and lightnesses of red and green, all faithful to those of the original images, and which can therefore form images with faithful shadings and rich in stereoscopic effect.
2. Description of the Related Art
As is known in the art, interlayer effect or interimage effect can be utilized in order to improve the color reproducibility of color photographic photosensitive material. In the case of a color negative photosensitive material, the color emission of a red-sensitive layer in white exposure can more be inhibited than that in red exposure by applying development-inhibiting effect from a green-sensitive layer to the red-sensitive layer. In the case of color negative paper, the interlayer effect achieves cyan-dye formation in a density higher in the case where the paper is red-exposed than in the case where the paper is gray-exposed. It is because the gradation is balanced such that gray will be reproduced on the color print when the paper is exposed to white light. As a result of this, red of higher saturation can be reproduced on the print, with the cyan dye formation greatly inhibited. For the same reason, green of high saturation can be reproduced on the print by applying development-inhibiting effect from the red-sensitive layer to the green-sensitive layer.
Various methods are known which work to promote the interlayer effect. One of them is to make use of the iodine ions released from the silver halide emulsion during development. In the method, a layer containing much silver iodide is used as layer for providing interlayer effect, whereas a layer containing less silver iodide is used as a layer for receiving the interlayer effect. Another known method of promoting the interlayer effect is disclosed in JP-A-50-2537 ("JP-A" means Published Unexamined Japanese Patent Application). In this method, a coupler is added to the layer providing the interlayer effect, said coupler releasing a development inhibitor when it reacts, in a paraphenylenediamine-based color developing solution, with the oxidation product of the developing agent. Still another known method of promoting interlayer effect is the so-called "automatic masking method," in which a colored coupler is added to an uncolored coupler, thereby masking the unnecessary absorption of the dye in the uncolored coupler. More specifically, the colored coupler can be added in an amount more than required to mask the unnecessary dye absorption, thus accomplishing the same effect as the interlayer effect.